BlackTreeCVE Intelligence
← Back to the CVE catalogue
Full vulnerability report · 2018
CVE-2018-8639High confidence

Microsoft Windows Win32k Improper Resource Shutdown or Release Vulnerability

Microsoft · Windows

7.8HighCVSS 3.1
Recommended action
Patch now

CISA confirms exploitation in the wild and lists 2025-03-24 as the remediation due date.

Patch available
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityHighOperational priority:Critical, raised one band.upgradedsince 3 Mar 2025

Evidence used

  • CISA confirms exploitation in the wild.
  • Exploitation requires an existing local or physical foothold with privileges.
  • EPSS is 22.18% for the current model date.

Compensating controls

  • Validate the affected product branch and deploy the verified fixed release.
  • Restrict local access and enforce least privilege on affected hosts.
  • Increase monitoring for the attack path and post-exploitation behaviour described in the report.

Verification

  1. Confirm that the asset runs Microsoft Windows and falls inside the recorded affected range.
  2. Verify the installed build against the product-specific fixed version after deployment.
  3. Validate exposure, authentication requirements and compensating controls in the actual environment.
  4. Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Mitigation target: Within 3 daysRemediation target: Within 90 days

This automated reassessment organises public evidence. It does not know asset exposure, business impact or control effectiveness and does not replace CVSS or a human risk decision.

Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Choose official national sources for this report. Each advisory shows its original language. Your selection is remembered on this device and included in shared links.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2018-20250

CISA KEV mirrored by ENISA

An elevation of privilege vulnerability exists in Windows when the Win32k component fails to properly handle objects in memory, aka "Win32k Elevation of Privilege Vulnerability." This affects Windows 7, Windows Server 2012 R2, Windows RT 8.1, Windows Server 2008, Windows Server 2019, Windows Server 2012, Windows 8.1, Windows Server 2016, Windows Server 2008 R2, Windows 10, Windows 10 Servers. This CVE ID is unique from CVE-2018-8641.

EUVD state
Present in the current official mapping
Known exploitation
Recorded by ENISA since 3 Mar 2025. Evidence sources: cisa_kev.
ENISA score
8.4 · CVSS 3.1
Advisory evidence
No linked advisory details stored yet
Recommended actionPatch now

CISA confirms exploitation in the wild and lists 2025-03-24 as the remediation due date.

Patch available
01

What, why and how

Microsoft Windows Win32k contains an improper resource shutdown or release vulnerability that allows for local, authenticated privilege escalation. An attacker who successfully exploited this vulnerability could run arbitrary code in kernel mode.

What

Microsoft Windows Win32k contains an improper resource shutdown or release vulnerability that allows for local, authenticated privilege escalation. An attacker who successfully exploited this vulnerability could run arbitrary code in kernel mode.

Why

The product does not release or incorrectly releases a resource before it is made available for re-use.

How

An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may execute code or commands in the affected security context.

What

Microsoft Windows Win32k contains an improper resource shutdown or release vulnerability that allows for local, authenticated privilege escalation. An attacker who successfully exploited this vulnerability could run arbitrary code in kernel mode.

Why

The product does not release or incorrectly releases a resource before it is made available for re-use.

How

An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may execute code or commands in the affected security context.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
Confirmed in the wild

CISA added this CVE to its Known Exploited Vulnerabilities catalogue on 2025-03-03. Known ransomware campaign use is recorded.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
local access → Improper Resource Shutdown or Release → execute code or commands in the affected security context
Attack surface
Local
Privileges required
Low: a basic authenticated account is required
User interaction
None
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-404 ↗

CWE-404: Improper Resource Shutdown or Release. The product does not release or incorrectly releases a resource before it is made available for re-use.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVLocalAttack vector: The attacker needs local access to the vulnerable system.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRLowPrivileges required: The attacker needs basic user-level privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CHighConfidentiality impact: A successful attack can cause a major loss.IHighIntegrity impact: A successful attack can cause a major loss.AHighAvailability impact: A successful attack can cause a major loss.
Post-exploitation / living off the land
After compromise, an attacker may use built-in shells, scripting engines, scheduled tasks and native network utilities for discovery, persistence or movement. This is a plausible LoTL path, not evidence that it has occurred for every attack.
Remote code executionPrivilege escalationCWE-404CISA KEV
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

ENISA EUVD · EUVD-2018-20250Known-exploited evidence recorded

An elevation of privilege vulnerability exists in Windows when the Win32k component fails to properly handle objects in memory, aka "Win32k Elevation of Privilege Vulnerability." This affects Windows 7, Windows Server 2012 R2, Windows RT 8.1, Windows Server 2008, Windows Server 2019, Windows Server 2012, Windows 8.1, Windows Server 2016, Windows Server 2008 R2, Windows 10, Windows 10 Servers. This CVE ID is unique from CVE-2018-8641.

Official EUVD record ↗
CERT-FR · French · CERTFR-2018-AVI-596Multiples vulnérabilités dans Microsoft Windows

De multiples vulnérabilités ont été corrigées dans Microsoft Windows . Elles permettent à un attaquant de provoquer une atteinte à la confidentialité des données, une élévation de privilèges, un déni de service et une exécution de code à distance.

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2018-011995複数の Microsoft Windows 製品における権限を昇格される脆弱性

複数の Microsoft Windows 製品には、Win32k コンポーネントがメモリ内のオブジェクトの適切な処理に失敗した場合、権限を昇格される脆弱性が存在します。 ベンダは、本脆弱性を「Win32k の特権の昇格の脆弱性」として公開しています。 本脆弱性は、CVE-2018-8641 とは異なる脆弱性です。

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2018-011948複数の Microsoft Windows 製品における権限を昇格される脆弱性

複数の Microsoft Windows 製品には、Windows カーネルモードドライバがメモリ内のオブジェクトの適切な処理に失敗した場合、権限を昇格される脆弱性が存在します。 ベンダは、本脆弱性を「Win32k の特権の昇格の脆弱性」として公開しています。 本脆弱性は、CVE-2018-8639 とは異なる脆弱性です。

Official advisory ↗
KISA KrCERT/CC · Korean · KNVD-4975MS 12월 보안 위협에 따른 정기 보안 업데이트 권고

- 권한상승 취약점(CVE-2018-8599,CVE-2018-8611,CVE-2018-8639,CVE-2018-8641) - 정보노출 취약점(CVE-2018-8477,CVE-2018-8514,CVE-2018-8595,CVE-2018-8596,CVE-2018-8639)

Official advisory ↗
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Patch available
Affected
Fixed
An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
Action
Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
Workaround
No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
04

Evidence and provenance

Published 12 Dec 2018 · Last source change 21 Oct 2025, 23:45 UTC · CWE-404 · Improper Resource Shutdown or Release

CVE recordCVE.org · 5.1
CVSS sourceNIST NVD
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-09-01
European sourceENISA EUVD · EUVD-2018-20250
Product sourceCISA KEV
Remediation sourceCVE/CNA references
CWE sourceCISA ADP
NVD statusNVD enriched

Core structured fields are present and their contributing authorities are shown above.

Material change intelligence

What changed after publication

View recent updates ↗
  1. ENISA known-exploited stateENISA EUVD now records this CVE in its known-exploited dataset.
    Before
    not listed in ENISA EUVD known-exploited dataset
    After
    listed in ENISA EUVD known-exploited dataset (EUVD-2018-20250)
    ENISA EUVD ↗
  2. ENISA EUVD mappingEUVD-2018-20250 was added to the official ENISA EUVD mapping for this CVE.
    Before
    not recorded
    After
    {"euvdId":"EUVD-2018-20250"}
    ENISA EUVD ↗
  3. Affected versionsThe structured affected or fixed version information changed.
    Before
    32-bit Systems Service Pack 1; x64-based Systems Service Pack 1; (Server Core installation); Windows RT 8.1; 32-bit Systems Service Pack 2; 32-bit Systems Service Pack 2 (Server Core installation); Itanium-Based Systems Service Pack 2; x64-based Systems Service Pack 2 · Fixed: An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
    After
    Windows 7: 32-bit Systems Service Pack 1, x64-based Systems Service Pack 1; Windows Server 2012 R2: (Server Core installation); Windows RT 8.1: Windows RT 8.1; Windows Server 2008: 32-bit Systems Service Pack 2, 32-bit Systems Service Pack 2 (Server Core installation), Itanium-Based Systems Service Pack 2, x64-based Systems Service Pack 2, x64-based Systems Service Pack 2 (Server Core installation); Windows Server 2019: (Server Core installation); Windows Server 2012: (Server Core installation); Windows 8.1: 32-bit systems, x64-based systems; Windows Server 2016: (Server Core installation); Windows Server 2008 R2: Itanium-Based Systems Service Pack 1, x64-based Systems Service Pack 1, x64-based Systems Service Pack 1 (Server Core installation); Windows 10: 32-bit Systems, Version 1607 for 32-bit Systems, Version 1607 for x64-based Systems, Version 1703 for 32-bit Systems, Version 1703 for x64-based Systems, Version 1709 for 32-bit Systems, Version 1709 for ARM64-based Systems, Version 1709 for x64-based Systems, Version 1803 for 32-bit Systems, Version 1803 for ARM64-based Systems, Version 1803 for x64-based Systems, Version 1809 for 32-bit Systems, Version 1809 for ARM64-based Systems, Version 1809 for x64-based Systems, x64-based Systems; Windows 10 Servers: version 1709 (Server Core Installation), version 1803 (Server Core Installation) · Fixed: An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
    CNA ↗
  4. Vendor guidanceAuthoritative vendor guidance changed: added patch: portal.msrc.microsoft.com/CVE-2018-8639; added remediation: portal.msrc.microsoft.com/CVE-2018-8639.
    Before
    no authoritative guidance recorded
    After
    patch: portal.msrc.microsoft.com/CVE-2018-8639 · remediation: portal.msrc.microsoft.com/CVE-2018-8639
    portal.msrc.microsoft.com ↗
  5. Affected versionsThe structured affected or fixed version information changed.
    Before
    32-bit Systems Service Pack 1; x64-based Systems Service Pack 1; (Server Core installation); Windows RT 8.1; 32-bit Systems Service Pack 2; 32-bit Systems Service Pack 2 (Server Core installation); Itanium-Based Systems Service Pack 2; x64-based Systems Service Pack 2 · Fixed: No fixed version is explicitly recorded in the structured CVE data.
    After
    32-bit Systems Service Pack 1; x64-based Systems Service Pack 1; (Server Core installation); Windows RT 8.1; 32-bit Systems Service Pack 2; 32-bit Systems Service Pack 2 (Server Core installation); Itanium-Based Systems Service Pack 2; x64-based Systems Service Pack 2 · Fixed: An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
    CNA ↗
  6. Remediation statusRemediation status changed from Awaiting fix to Patch available.
    Before
    Awaiting fix
    After
    Patch available
    portal.msrc.microsoft.com ↗
  7. CVSS scoreCVSS score changed from 8.4 (CVSS 3.1 · CISA ADP · CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H) to 7.8 (CVSS 3.1 · NIST NVD · CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H).
    Before
    8.4 (CVSS 3.1 · CISA ADP · CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)
    After
    7.8 (CVSS 3.1 · NIST NVD · CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)
    NIST NVD ↗
  8. Catalogue recordCVE added to the BlackTree catalogue.
    CNA ↗
Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Added to CISA KEV
Fixed release or patch reference recorded
ENISA EUVD · EUVD-2018-20250↗CISA KEV record↗Patch or update reference↗CVE authority or vendor reference↗Official CVE record (CNA and ADP data)↗NVD record↗
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2018-8639 · cve.blacktree.nl